Effects of Brain Piqure on the First and Second Ovipositions of the Hen's 2-Egg Sequence

Abstract

Summary

Piqure of the hen's brain evoked premature lay of the C₁ and C_t eggs of a 2-egg sequence during restricted periods which stood in the same relationship to each other as the periods of normal lay for the respective eggs. C_t lay was advanced by piqure of any of several brain sites, but C₁ lay was advanced only by piqure of the pre-optic brain. The frequency of premature lay in relation to time of preoptic piqure differed markedly for the two eggs.